Trends in Green Chemistry
The use of synthetic chemicals is ubiquitous, from cars to clothes, electronic gadgets to construction materials, handbags to skincare products, and what not. However, the growing adoption of synthetic chemicals across various end-use industries is putting a strain on the environment, primarily contributing to climate change, toxic pollution, and plastic waste problems that threaten human and planetary health. According to several research studies, the chemical pollution has surpassed the safe limit for humanity and threating the global ecosystem upon which the mankind depends.
The use of synthetic chemicals has increased 50-fold since the 1950s and is expected to become three-fold by 2050. Hence, the chemical industry needs to undergo a radical change for a sustainable future. Mounting pressure from consumers and governments to achieve sustainability in the chemical production, depleting levels of oil and gas reserves, and adverse effects of climate change have led to an increased focus of chemical manufacturers towards green chemistry.
Green chemistry, also known as sustainable chemistry, involves the sustainable production of chemical products and processes that reduce or stop the use and production of hazardous substances. Growing R&D initiatives in the field of green chemistry and technological innovation have led to increasing application of green chemistry for the reduction of CO2, as a raw material for chemical synthesis, microwave, electromechanical and ultrasound synthetic methods, solvent free reactions, phytoremediation, waste management and wastewater, eco-friendly dyes and pigments, innovative food products, renewable energy sources, etc.
As the decarbonization projects are increasing and the awareness of the market is growing, chemical manufacturers are increasingly investing in R&D, funding, partnerships, or strategy changes, which is resulting into the growth of green chemistry. The practice of green chemistry is also beneficial for economy and society as it provides a strong encouragement to develop sustainable products and processes.
Here are the top trends dominating the green chemistry industry.
- Use of Environmentally Benign Solvent Systems
Chemical industry consumes large quantities of organic solvents such as hydrocarbons, esters, alcohols, glycols, etc. due to their ability to dissolve or disperse other chemical substances, usually with fast evaporation and thus meet expectations of the finished product manufacturers. Their use creates large amounts of waste, air pollution, and other health impacts. Most of these solvents have synthetic origin or are derived from crude oil or olefins. This has necessitated the need for efficient alternatives or removing solvents altogether. Organic solvents react in the atmosphere in sunlight and produce air pollutant known as ground-level ozone.
Many new green solvents have emerged in recent years, which are now being used as alternative to crude oil derivatives or synthetics, driven by government regulations and concerns regarding environmental preservation. The renewable solvents are environment friendly as their origin is not from petrochemicals. The bio-based solvents deliver excellent performance, both financially and environmentally. Most of these bio-based solvents are derived from sugar, corn, or beet and do not release any toxic by-products or volatile organic compounds during manufacturing. Ethanol is predominantly used bio-based chemical solvent used for the commercial production of goods such as detergents, shampoos, cosmetics, lotions, soaps, and other consumer products.
Cyrene has emerged as a new safer and bio-based potential alternative to harmful and toxic chemical. The eco-friendly solvent has been developed by synthesizing renewable cellulose waste, via a manufacturing process that is almost energy neutral and releases water to the environment. The green solvent has similar physical property as that of the dipolar aprotic organic solvent.
- Rising Application of Nanoparticles as Synthetic Catalysts
Nanoparticles are one of the most common nanomaterial forms with specific functional properties that lead to their application in various areas. Nanoparticles are useful for catalysis since they have high relative surface area, lower energy consumption, environment-friendly behaviour. These particles are widely used for organic synthesis, especially in a commercial production setting as they enable chemical products to be produced at a lower cost.
Nanoparticle synthesis using microorganisms and plants by green synthesis is an eco-friendly method to devour and accumulate inorganic metal ions. These biosynthesized metallic ions have a range of pharmaceutical implications including delivery of drugs or genes, detection of pathogens or proteins, and tissue engineering. Green and valuable synthetic techniques using Cyanobacteria bacteria (blue green algae) have attracted the attention of researchers for the synthesis of nanoparticles. Cyanobacterial technology is timesaving for large-scale production at ambient temperatures as they grow at a much faster rate compared to the plants and could easily be manipulated as needed. Algae is also considered to possess heavy metals, which can be utilized for the biogenic synthesis of metallic nanoparticles of diverse shapes, be it tetrahedral, decahedral, and icosahedral. Thus, green synthesis technology presents a clean, non-toxic, and eco-friendly technique for the synthesis of nanoparticles on a large scale.
- Generating Wealth from Waste
The idea of transforming residual streams such as food waste to fuels and useful compounds has been gaining prominence in recent years, owing to advancement in technologies and rapidly growing need for clean energy. Organic waste sources hold immense potential to act as an alternative resource for producing high-value fuels and chemicals. Food waste contributes significantly to the global waste and greenhouse gas emissions. One of the most innovative and eco-friendly ways of dealing with organic waste is through anaerobic digestion. Microbial chain elongation is a biotechnological process that converts volatile fatty acids into an electron donor, especially, ethanol, into more valuable medium chain fatty acids.
Researchers have explored reverse β-oxidative pathway, opposite of metabolic pathway organisms to break down fatty acids derived from foods and produce chemicals and polymer building blocks. Chain elongation method has proven to be effective in developing chemicals used in laboratory bioreactors, a process that occurs naturally in soils. Currently, researchers are examining the extent of natural chain elongation and how processes vary according to the particular biogeochemical characteristics of soil composition to gauge the prevalence of chain elongation in anaerobic soil microorganisms and their role in microbial ecology.
- Innovation in Plastics
As the plastic pollution continues to remain a threat to our environment, researchers are constantly developing new alternatives to plastics. Researchers have developed a bacterium known as Ideonella sakaiensis that has the ability to consume PET, or polyethylene terephthalate in a month. Earlier PET was considered to be non-biodegradable due to its origin in petroleum, but the bacteria is currently under investigation to determine the conditions for their enzymes to properly break down the materials. Besides, bioplastics for food packaging has been emerging as a viable alternative to single-use plastics that are also carcinogenic. Bioplastics decomposes in two years within a compost bin, which can prevent a lot of plastic pollution. Currently, scientists are discovering correct composites need to turn the cellulose into fluid plastic, which would make them ideal for non-toxic packaging of food items.
Many innovators have designed sustainable and eco-friendly plastics that are making an impact to combat plastic pollution. Angirus offers sustainable bricks composed from recycled plastic waste that weigh less than 1 kg but has equivalent strength as clay bricks. Mi Terro have created home compostable biomaterials made from plant-based agricultural waste as an alternative to polyethylene plastics. New York-based start-up has developed edible version of single-use plastic straws, one of the biggest sources of plastic pollution in oceans. The edible straws are made up of seaweed, considered a suitable alternative to plastic due to its renewable production.In the coming years, more such innovation in the green chemistry and advent of new technologies could be witnessed.
